1. Field of the Invention
The present invention relates to a novel anti-cancer compound identified in mycelium of Antrodia camphorata, the methods of cultivation, and applications of the said compound. To be more specific, the extracted compound is a bioactive anti-cancer compound that can inhibit the proliferation of hepatoma liver cancer cells and provide protection against liver cancer.
2. Description of the Prior Art
Antrodia camphorata is a medicinal fungus growing inside the Cinnamomum kanchirai Hayata, Lauraceae trunk, a native species tree found in Taiwan. Antrodia camphorata has been reported to have many medicinal properties including anti-oxidant, anti-inflammation, and anti-cancer properties (Chang and Chou, 2004; Mau, Huang; Huang and Chen, 2004; Song and Yen; 2003; Hseu, Chang, Hseu, Lee, Yech, and Chen, 2002; Shen, Chou, Wang, Chen, Chou, and Lu, 2004 ; Ao et al., 2009). This particular type of fungus was widely used as a treatment drug for liver-associated diseases in traditional medicine. Recently, the anti-cancer activity of Antrodia camphorata, particularly the anti-liver cancer activity, has attracted great interests.
Many compounds identified in Antrodia camphorata were demonstrated to exhibit anti-cancer activities. Lien et al. have purified 4,7-dimethoxy-5-methyl-1,3-benzodioxole from dry fruiting body of Antrodia camphorata and discovered that this compound can inhibit the proliferation of human colon epithelial cells (Lien et al., 2009). In addition, 24-methylenelanosta-7,9-(11)-diene-3β, 15α-diol-21-oic (MMH01), another compound identified in Antrodia camphorata mycelium, was shown to inhibit the growth of human leukemia cancer cells (U937) and pancreatic cancer cells (BxPC3) (Chen, Chou, and Chang, 2009). Aside from their anti-cancer activities, some compounds isolated from Antrodia camphorata have also displayed anti-inflammatory activities. Yang et al. (2009) purified 5 different compounds from Antrodia camphorata which include antroquinonol B, 4-acetyl-antroquinonol B, 2,3-(methylenedioxy)-6-methyl benzene-1,4-diol, 2,4-dimethoxy-6-methyl-benzene-1,3-diol and antrodin D, and found that they can efficiently inhibit NO production and exhibit certain anti-inflammatory effects.
Due to the high medicinal value and slow growth rate of Antrodia camphorata, the fruiting body of Antrodia camphorata is on high demand nowadays. In order to meet with the market demand of this rare fungus, many approaches have been explored and industrial-level production of Antrodia camphorata mycelium by using liquid culture medium has been developed (Shin, Pan, and Hsieh et al. 2006). While the medicinal effects of Antrodia camphorata have drawn much attention, limited studies are available in terms of identification and characterization of these bioactive anti-cancer compounds found in mycelium. Nakamura et al. discovered five derivatives of malic acid and succinic acid from mycelium of Antrodia camphorata, and demonstrated that these compounds have cytotoxic effects on LLC lung cancer cell line and the EC50 are between 3.6 and 20 μg/mL (Nakamure et al., 2004). Studies conducted by Cheng, Huang, Chang, Wang and Lu have suggested that polysaccharides isolated from Antrodia camphorata can suppress angiogenesis by down regulating the expression of cyclin D1 through inhibition of vascular endothelial growth factor receptor (VEGF receptor) signaling.
Hepatoma is the leading lethal cause of malignant cancers in China, Taiwan, Korea and south of the Sahara in Africa (Seow, Liang, Leow and Chung, 2001; Kern, Breuhahn and Schirmacher, 2002). Previous studies have shown that mycelium of Antrodia camphorata can protect the liver from damage caused by alcohol, CCl4 and lipopolysaccharides (Dai et al., 2003; Lu et al., 2007; Hsiao et al., 2003; Song and Yen, 2003; Hattori and Sheu, 2006; Ao et al., 2009). Guo et al. have also revealed that mycelium of Antrodia camphorata can reverse the liver fibrosis induced by dimethylnitrosamine, DMN (Guo et al. 2002). Moreover, in vitro study have proved that the extract of Antrodia camphorata mycelium can inhibit the proliferation of hepatoma liver cancer cells and the IC 50 of HepG2 and Hep3B cells are 49.5 and 62.7 μg/mL, respectively (Song, Hsu and Yen, 2005). Pan et al. cultivated the Antrodia camphorata using a 5-ton fermenter and have demonstrated that the extract of Antrodia camphorata mycelium can significantly reduce the IC50 of HepG2 hepatoma liver cancer cells to 4.25 μg/mL (Pan et al., 2008). While accumulated evidence has strongly suggested the anti-hepatoma activities of Antrodia camphorata, the definite bioactive anti-cancer compounds remain unclear. Therefore, to further identify and characterize the bioactive, anti-cancer compounds found in Antrodia camphorata, the inventor(s) have successfully 1) developed a new approach for Antrodia camphorata cultivation and purification, 2) identified the definite bioactive anti-cancer compound and 3) verified its use for anti-cancer treatments.